Electronic equipment is commonly implemented using digital technology instead of analog technology, while signals to be processed by the electronic equipment are often initially analog (e.g. radio signals, sensor output signals, image captures, etc.). Typically, the more advanced the digital technology gets the more demanding the task of converting an analog signal to a digital signal suitable for the digital technology implementation becomes.
Conceptually, an analog-to-digital converter (also denoted ADC or A/D converter) is very well know in the art as well as its basic functionality (sample-and-hold, quantization) and will not be elaborated on further herein.
It is often beneficial, or even necessary, that the analog-to-digital conversion fulfills certain requirements. Such requirements may, for example, comprise accuracy requirements (in terms of sampling speed and/or quantization precision for each sample) and/or energy consumption requirements. The quantization precision may, for example, comprise a quantization range and/or a maximum deviation from the analog signal sample value. It may often be cumbersome to fulfill all requirements of the analog-to-digital conversion, in particular if the implementation of the analog-to-digital conversion should be reasonably cheep and/or with a small circuit footprint. Typically, if an ADC is designed to fulfill requirements of a particular application it may be unsuitable for use in another application.
Therefore, there is a need for arrangements that enable adaptation of the operation of an ADC to a particular application.
US 2011/0148682 A1 discloses a predictive analog-to-digital converter system that includes a sampling section producing a sampled analog input signal with a summer section combining the sampled analog input signal and an analog prediction signal to produce an analog prediction error signal. An error analog-to-digital convertor digitizes the analog prediction error signal. A second summer is coupled to the digital error signal output (from the error analog-to-digital convertor) and a digital prediction signal, and generates a digital output signal. A feedback section is coupled to the digital output signal and providing the digital prediction signal and the analog prediction signal.